HRV for Apple Watch

Your calm isn't anyone else's average.

Vela measures your heart rate variability (SDNN) directly on your Apple Watch and builds a baseline that's yours — not a generic population threshold. All the computation happens on the watch. Nothing ever passes through our servers, because we don't have any.

SDNN · LIVE AT REST
population noise your baseline settles

About the name

Why “Vela”

“Vela” is also the Spanish word for a boat's sail — from the Latin velum. A sailboat doesn't fight the wind: it reads it and adjusts course. That's the idea behind the app. Instead of comparing you to an external standard, Vela reads your own personal baseline and helps you understand your own patterns. Stress isn't something to fight — it's something to read and adjust to.

Why the average doesn't work

25 ms of HRV can be high for you and low for someone else.

HRV varies enormously between people. A population threshold treats everyone the same — which is exactly why it's almost always wrong. Vela builds your own baseline from your real history: if you already have HRV data on your Apple Watch, it can start from day one; if you're new, it takes 7–14 days to settle.

Generic population threshold
Individual samples
Your personal baseline

How it works

Four decisions, made to not change our minds.

On-device

All the computation happens on your Watch. HealthKit provides the data, the watch does the rest. No HRV data ever leaves your device toward a Vela server.

Your iCloud, not ours

Syncing uses your own iCloud account via CloudKit. Vela doesn't host your data anywhere — it can't, because it has nowhere to.

No subscription. Ever.

No monthly or yearly fees. Vela is free today. In the future there will be a paid Pro version — never a subscription.

Accessible by default

VoiceOver, Dynamic Type, Reduce Motion and 9 languages: Spanish, Catalan, Basque, Galician, English, French, German, Italian, and Portuguese.

On your wrist

One score, one state, one trend.

Color and text label always go together — designed with color blindness in mind too. Every score is explained: which range counts as “Normal”, when it becomes “High”, and why.

Three Vela screens on Apple Watch Ultra: current stress score with Normal status, weekly trend with the day's average, and a screen explaining the Normal and High ranges.

Quick tour

Three screens, each with a single job.

Vela's main screen showing a stress score of 68, Normal status, calculated in the moment.
Current score

One number, one state, computed entirely on the watch — no waiting for anything to sync.

Trend chart with the day's average stress and hourly readings, compared against the personal baseline.
Trend

Every reading of the day, compared against your own dashed line — not anyone else's.

Screen explaining the stress ranges: Normal between 40 and 69, High between 70 and 100.
Ranges explained

No cryptic numbers: every range says what it means and what to expect.

Getting started

We ask permission before measuring anything.

Vela asks for access to your HRV explicitly, not in the fine print. And if you're new to measuring HRV, it tells you how long until you have a reliable baseline — without pretending it knows who you are on day one.

Vela's onboarding flow on Apple Watch: a welcome screen, an explicit request for access to heart rate variability data, and a baseline-building screen showing 7 days remaining.

Download it today

No subscription. Ever.

Vela is available for free on the App Store for Apple Watch.